Methods for adjusting a shock absorber and strut assembly

ABSTRACT

Methods for easily adjusting a shock and strut assembly to modify the ride height of a vehicle by providing one or more spacers to be placed between the lower spring seat mount and the spring seat plate that rests upon it in order to raise the ride height of a vehicle. Embodiments include a unique location for a lower spring seat mount. The position of the lower spring seat mount may be lowered to reduce the ride height of the vehicle, and one or more spacers may be inserted above the lower spring seat mount to raise the ride height of the vehicle.

This is a continuation of U.S. Utility Application No. 12/258,929 filedon Oct. 27, 2008, now U.S. Pat. No. 8,070,171, which claims the benefitof U.S. Provisional Application No. 61/001,153 filed on Oct. 30, 2007,both of which are incorporated herein in their entirety by thisreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to automotive suspension technology, andmore specifically to shock absorber and strut assemblies and methods forusing such assemblies in aftermarket modification.

2. Description of the Related Art

Shock absorbers have been used as a part of suspension systems forautomobiles for many years as a means to lessen vibration of driving onrough road surfaces and to increase ride quality. Most strut assembliescommonly used on automotive vehicles include a shock absorber (dampener)with a coil spring. These strut assemblies are attached to the undersideof a body of a vehicle and connect to the suspension. The upper mountingunit of such a strut assembly has a spring mounting unit and shockabsorber shaft connection point which secures to the underside of thevehicle. The upper end of the spring sits in the upper mounting unit andextends downward surrounding the shock absorber. The spring mounts to alower spring seat which is fixed to the exterior of the shock absorber.The shock absorber continues downward and connects to a steering knuckleor other component of the vehicle suspension. The combination of thespring and shock absorber lessens the vibration created while driving,and further plays a significant role in ride height. The coil springsare a given length when compressed with the load of the vehicle. Thespring raises the riding height of the vehicle based on the location ofthe lower spring seat on the shock absorber. Depending on the vehicle,such a distance has been calculated, and the lower spring seat isfixedly attached to the shock absorber in a location to effectuate thedesired lift in the vehicle.

Aftermarket modification of vehicles, specifically of suspensioncomponents, is a popular and ever-growing market. Markets have arisenfor both the raising and lowering of vehicle ride height for bothaesthetic purposes and for performance. Many cars and trucks are loweredand have modified suspension systems for improved handling in streetapplications; and many vehicles, including trucks, sport utilityvehicles, and jeeps have raised ride heights and stronger suspensioncomponents for off-road applications. Many times the shocks and springsof such vehicles are replaced to change the handling characteristics ofthe vehicle. Softer or firmer coil springs may replace factory units inorder to effectuate the ride preference of the driver. In addition, manydifferent types of shock absorbers can be used offering the driverdifferent options. When aftermarket components are used, they do notnecessarily meet the dimensions of the factory units, and adjustment ofthe suspension may be necessary to obtain the desired ride height.

Aftermarket modifications, especially those which raise or lower thechassis of a vehicle, create unique problems not usually encounteredwith an unmodified vehicle. For instance, many modifications can becombined, thereby different dimensions and tolerances within thesuspension system can be created which are not normally encountered.Further, some modifications may affect ride height by interchangingdifferent components of the suspension of a vehicle. When this occurs,it may be desired to modify the ride height, but there is no simplemethod to effectuate such a solution. To compound the issue, labor onsuspension systems can be difficult and time consuming. Accordingly,many consumers may be discouraged to modify the suspension of a vehicledue to the effort or the expense in labor costs to hire someone toinstall and properly configure an aftermarket suspension.

An example of a strut assembly that may be adjusted to change thevehicle ride height is disclosed in U.S. Pat. No. 6,902,045. However,the adjustment assembly disclosed involves the use of a ring gear thatis adjusted by way of an outwardly protruding knob. Such a systemincludes inherent problems with regard to locking the ring gear inplace, unintentional adjustment of the ring gear by accidental contactwith the outwardly protruding knob, and further the difficulty to makeexact adjustments in height. Additionally, wear on the ring gear maylead to failure thereby endangering the passengers of the vehicle.

Another strut assembly that allows for the adjustment in ride height isdisclosed in U.S. Pat. No. 7,237,780. The device described in thispatent uses a system involving two springs to adjust the ride height.This design includes a greater number of components thereby increasingcosts and allowing for more potential points of failure.

It is therefore desirable to provide a shock absorber and strut systemthat is capable of being easily adjusted to raise or lower the rideheight of the vehicle without the need to adjust or replace othercomponents of the suspension.

SUMMARY OF THE INVENTION

The present invention includes methods and apparatus for easilyadjusting shock and strut assemblies to modify the ride height of avehicle. A typical factory shock and strut assembly includes a shockabsorber (dampener) having a piston unit with a piston shaft extendingfrom the top end of the shock absorber. A spring seat mounting unit istypically attached to the piston unit and a coil spring is typicallysecured between an upper spring seat and the spring seat mounting unit.The spring seat mounting unit typically has a spring seat mountextending radially outward from the shock absorber, to prevent downwardmovement of a lower spring seat plate. Methods and apparatus of thepresent invention provide for placing one or more spring seat spacersbetween the spring seat plate and the spring seat mount in order toraise or lower the ride height of a vehicle, thereby altering the rideheight of the vehicle.

The present invention includes an aftermarket shock and strut assembly.Some of the components of these embodiments can be the unmodifiedoriginal equipment in order to save cost, and prevent the duplication ofparts. These embodiments include a shock absorber having a pistonassembly with a piston shaft extending axially in one direction and anopening or other means for attachment connected to the other end of thepiston assembly. In some embodiments, the shaft has a threaded endallowing for securing the shock absorber to the vehicle. The opening orother means for attachment at the other end of the shock absorber allowsfor securing the shock absorber to a steering knuckle, fork, or othercomponent of the suspension of a vehicle. In some embodiments, theopening is a transversely oriented cylinder which accepts a bushing andbolt for connection to a suspension component.

In embodiments of the invention, a coil spring is secured around a shockabsorber using an upper and a lower spring seat. The upper spring seatreceives an upper end of the spring, and may be secured to the pistonshaft extending upwardly from the shock and strut assembly.Alternatively, the spring seat may be attached to or incorporated into aportion of the vehicle to receive the upper end of the spring. Whenused, the upper spring seat can be created in many differentconfigurations. In most embodiments, the upper spring seat is a platewith a relatively flat surface at least as large as the diameter of thecoil spring designed to receive the upper end thereof. The upper springseat can have lips, indentations, and/or other projections on its innerand outer surfaces to conform to and prevent the movement of the springbeyond the plate. In other embodiments, the upper spring seat may beprovided as a plurality of radial projections which hold the upper endof a spring in place. It is to be appreciated that the upper spring seatcan be secured to an upper portion of the shock absorber, the vehicle,or to the suspension.

In embodiments of the invention, the lower spring seat is provided as amounting unit that may comprise a spring seat mount, a lower spring seatplate, and one or more spacers. In these embodiments, the exterior ofthe piston assembly of the shock absorber has a spring seat mountextending radially outward from the shock absorber. This spring seatmount may be an outward indentation, lip or ridge, or a plurality ofindentations, lip segments or ridges designed to prevent the lowerspring seat plate and/or spacers from sliding past the spring seatmount.

In these embodiments, the lower spring seat is a plate with a relativelyflat surface at least as large as the diameter of the coil spring inorder to receive and support the spring. The seat can have lips,indentations, or other projections on its inner and outer surfaces toconform to and prevent the movement of the spring beyond the plate. Insome embodiments, the lower spring seat is a plurality of radialprojections which hold the lower end of a spring in place. The lowerspring seat has an interior opening that is about the same diameter asthe piston assembly so that the spring seat surrounds the pistonassembly but is stopped by and rests upon the ridge/lip/indentation(s)of the lower spring seat mount to prevent downward movement of the lowerspring seat.

In some embodiments, the spring seat mount of the present invention islocated at a position on the shock absorber that is ordinarily lowerthan that of the original equipment from the manufacturer. In theseembodiments, if the lower spring seat plate is slidably placed directlyon the lower seat mount, the spring will rest at a location lower thanthe original spring seat mount. This location of the lower spring seatplate and spring will lower the ride height of the vehicle due to thedifference in distance from the mounting location on the originalequipment and the spring seat mount of the present invention.

Embodiments of the present invention utilize one or more spacers placedbetween the lower spring seat mount and the lower spring seat plate toalter the lower position (mounting location) of the coil spring. Thespacers can be provided in the form of a washer, shim, or other rigiddevice that has an inner opening large enough to receive the shockabsorber, but small enough to be stopped by the ridge/lip/indentation(s)of the lower spring seat mount. The thickness of each spacer creates adistance between the lower spring seat mount and the lower spring seatplate. In some embodiments, one or more spacers can be employed byslidably lowering a first spacer on top of the lower spring seat mount;then, if additional spacers are desired, they are slidably placed on topof the spacer(s) already in place. Once a desired thickness is obtainedusing one or more spacers, the lower seat plate is then slidably placedon the top of the spacer(s). Therefore, the invention allows the user tomodify the spring height, and therefore ride height of the vehicle bythe addition or removal of spacers.

In alternative embodiments, spacers can be secured between the lowerspring seat mount and the lower spring seat plate without removing theshock absorber from the vehicle. In some embodiments, the spacers mayhave a plurality segments that may be placed around a shock absorber,and the segments be fixedly secured in place. In further embodiments,the spacers may have a plurality of hinged segments that may be closedaround the shock absorber with the ends of the segments of each spacerfixedly attached to each other to secure the spacer around the shockabsorber. In other embodiments, each spacer may be provided in the formof a disc having a central opening and a radial cut, so that the spacermay be slightly deformed along the cut as it is installed around theshock absorber above the lower spring seat mount. It is to beappreciated that the invention contemplates other embodiments of spacersthat may have parts that are attached together and/or inserted aroundthe shock absorber to provide spacing thickness above the lower springseat mount without requiring disconnection of the shock absorber.

In some embodiments all the spacers are of a uniform thickness (width)allowing for easy measurement of the change in height above the lowerspring seat mount based on the number of spacers used. For example, ifeach spacer is one half inch in height, stacking 2 spacers onto thelower spring seat mount will raise the effective position of the mountby one inch. In other embodiments spacers of various thicknesses(widths) may be used in order to fine tune the height achieved. Whilespacers of any appropriate thickness may be used, proper adjustments canordinarily be made using spacers having thicknesses between about 7 mmand about 23 mm (0.27 in. to about 0.91 in.). Other spacers may range inthickness from about ¼ inch to about one inch. Different colored spacersmay be used to identify different thicknesses, making it easy todetermine the total thickness from the colors of the spacers used.Further, graduated measurement markings may be placed on the shockabsorber body to allow a user to easily determine the change in heightfrom the lower spring seat mount due to the additions of spacers. It isto be appreciated that different combinations of thicknesses, types andcolors of spacers may be used in various embodiments of the invention,with or without additional markings on the body of the shock absorber.

The invention allows for the ride height of the vehicle to be raised,lowered, or to remain the original ride height without majormodifications to the suspension system. With the invention, a user caneasily and quickly correct or adjust the ride height of vehicle. Theinstallation of embodiments of the present invention is relativelysimple and takes no further effort than that required to replace theshock and strut assemblies with original equipment.

It is therefore an object of the present invention to provide shockabsorber and strut assemblies which can easily be modified to adjust theride height of a vehicle.

It is a further object of the present invention to provide shockabsorber and strut assemblies which can be modified to adjust the rideheight of a vehicle that are capable of bolt-on installation.

It is a further object of the present invention to provide methods andapparatus for adjusting the ride height of a vehicle.

Additional objects of the invention will be apparent from the detaileddescriptions and the claims herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an embodiment of an unmodified strut.

FIG. 2 is a side view of an embodiment of a strut of the presentinvention showing the lower spring seat mount and plate in a loweredposition relative to the position of a corresponding factory strut.

FIG. 3 is a side view of an embodiment of a strut of the presentinvention showing the lower spring seat plate in a raised position bythe use of spacers.

FIG. 4 is a side view of an alternative embodiment of an unmodifiedstrut.

FIG. 5 is a side view of an embodiment of a strut of the presentinvention showing a coil spring in which the position of a lower springseat plate has been raised using spacers.

FIG. 6 is a side view of another embodiment of a strut of the presentinvention showing a coil spring in which the position of a lower springseat plate has been raised using spacers.

DETAILED DESCRIPTION

Referring to the drawings wherein like reference characters designatelike or corresponding parts throughout the several views, and referringparticularly to FIG. 1, it is seen that a typical strut assembly 20includes a shock absorber assembly 21, and a lower spring mounting unit22. Such a strut assembly also includes an upper spring mounting unitand coil spring, neither of which is shown in FIG. 1. The shock absorberassembly is generally cylindrical in shape, consisting of a piston unit25 with a piston shaft 26 exiting the piston unit 25. The piston shaft26 has a means for securing the shaft 26 to the vehicle at its terminal27. This can be done in a manner commonly known in the art such as, butnot limited to, having a threaded end accepting a bolt, or the presenceof a hole for the insertion of a locking pin. The lower end of the shockabsorber assembly typically has a transversely positioned opening 30 forthe attachment of the lower end of the strut assembly to be secured to apart of the suspension of a vehicle, commonly a steering knuckle,although attachment may be made to other similar suitable structures ofthe vehicle suspension assembly, including forks, etc. The opening 30 isusually fitted with a bushing 31, further dampening the vibrationsreceived from the steering knuckle.

The lower spring mounting unit creates a base upon which a coil springsits, The lower spring seat plate 34 is generally flat and round inshape with indentations appropriately located to conform to the end of acoil spring to prevent movement of the spring when positioned on theseat. In a factory created strut, such as that depicted in FIG. 1, thelower spring seat mount (35) is often welded in place which securelyattaches the lower spring seat plate 34 in a permanently fixed position,preventing any adjustment in height of the lower spring seat plate.

FIG. 2 depicts a strut assembly having a lower spring seat mount (35)that is positioned lower than that shown in FIG. 1. As in FIG. 1, thelower spring seat plate 34 bears directly against the lower spring seatmount. The spring seat mount (35) prevents the spring seat plate 34 frommoving any lower on the piston unit 25. The placement of the spring (40)on this lowered spring seat plate 34 creates a greater distance from thelower spring seat plate 34 to the upper seat plate (affixed in proximityto the end of the piston shaft 26). The weight of the vehicle willcompress the exemplary shock absorber (and the spring) illustrated inFIG. 2 to a position that is lower than that shown in FIG. 1, therebycausing the vehicle to be lowered.

FIG. 3 depicts an exemplary strut assembly of the present inventionwhere spacers 38 have been inserted between the lower spring seat mount35 and the lower spring seat plate 34 to raise the location of thespring seat plate 34 with respect to the piston unit 25. The lowerspring mount 35 can be a ridge, lip or other structure extendingoutwardly from the piston unit 25 to prevent further downward movementof the lower spring seat plate 34. It should be noted that in theexemplary embodiment of FIG. 3, the spring seat mount 35 happens to beat the same height as the spring seat mount in the exemplary embodimentof FIG. 2, where the lower spring seat plate was lower than theexemplary embodiment of FIG. 1. With the addition of the spacers 38, thelower spring seat plate 34 may be moved to a raised position. Dependingon the desired height, one or more spacer(s) 38 can be placed on top ofthe spring seat mount 35. It is to be appreciated that spacers 38 may beof different thicknesses (heights) in order to fine tune the distance bywhich the lower spring plate is raised. Since the spring is compressedthe same by the weight of the vehicle, the higher placement of the lowerspring seat plate 34 using the spacer(s) 38 increases the ride height ofthe vehicle.

FIG. 4 depicts an exemplary strut assembly 20 including a coil spring 40and an upper spring seat plate 42. The lower end of the coil spring 40is secured by the lower spring seat plate 34, and the upper end of thecoil spring 40 is secured by the upper spring seat plate 42. In theembodiment shown in FIG. 4, the upper spring seat plate 42 is secured tothe piston shaft 26. The coil spring 40 maintains a relatively standarddistance when loaded under the weight created by the vehicle.Accordingly, the length of the strut assembly incorporates the totaldistance of the spring under load, and the portion of the springassembly on either end of the upper spring seat plate 42 and lowerspring seat plate 34.

FIGS. 5 and 6 depict exemplary strut assemblies 20 in which one or morespacers 38 have been inserted between the spring seat mount 35 and thelower spring seat plate 34. The spacers raise the location of the lowerspring seat plate 34 higher in relation to the spring seat mount 35.Accordingly, the bottom end of the coil spring 40 rests at a locationhigher in relation to that of the coil spring shown in FIG. 4 or 5. Theupper spring seat plate 42 remains in the same position in relation tothe strut assembly 20, however, the result of the spacers creates astrut assembly that is a greater length.

It is to be appreciated that different versions of the invention may bemade from different combinations of the various features describedabove. In particular, any number of spacers 38 (of the same or differentthicknesses), including using the apparatus without spacers, may be usedallowing the user to easily modify the ride height of the vehicle ineither an upward or downward direction.

It is to be understood that variations and modifications of the presentinvention may be made without departing from the scope thereof. It isalso to be understood that the present invention is not to be limited bythe specific embodiments disclosed herein, but only in accordance withthe appended claims when read in light of the foregoing specification.

What is claimed is:
 1. A method for adjusting the ride height of avehicle comprising: a. removing a strut assembly from the vehicle; b.removing a spring from a shock absorber of said strut assembly; c.removing a spring seat plate from said shock absorber; d. slidablyplacing a plurality of non-adjustable spacers on said shock absorberabove a fixedly attached spring seat mount, each such spacer having auniform axial height; e. placing said spring seat plate on an uppermostof said spacers; f. replacing said spring on said spring seat plate; andg. installing the strut assembly in said vehicle.
 2. The method of claim1 wherein said spacers each include a hinge.
 3. The method of claim 1wherein said spring seat mount has a substantially flat upper surface.4. The method of claim 1 wherein said spring seat mount comprises a liparound said shock absorber, said lip having an outside perimeter, andwherein each of said spacers has a central opening therein having aninternal diameter that is smaller than the outside perimeter of saidlip.
 5. The method of claim 4 wherein each of said spacers has anoutside perimeter that is greater than the outside perimeter of saidlip.
 6. The method of claim 1 wherein each spacer has the same height.7. The method of claim 1 wherein said spacers have different heights. 8.The method of claim 1 wherein said plurality of spacers are selectedfrom the group consisting of a spacer with a first height, a spacer witha second height, a spacer with a third height, and combinations thereof.9. The method of claim 1 wherein rotation of said spacers will notaffect vehicle ride height.
 10. The method of claim 1 wherein saidspring seat mount has an upper surface for abutting one of said spacers,said upper surface being perpendicular to an axis of said strutassembly.
 11. A method for adjusting the ride height of a vehiclecomprising: a. removing existing first strut assembly from the vehicle,said assembly comprising a first shock absorber having a first springseat mount, a first spring and a first lower spring plate; b. providinga second strut assembly, said second assembly comprising a second shockabsorber having a second spring seat mount that is positioned lower thanthe spring seat mount of said existing strut assembly, a second spring,and a second lower spring plate; c. removing said second spring fromsaid second shock absorber; d. removing said second spring seat platefrom said second shock absorber; e. slidably placing at least onenon-adjustable spacer on said second shock absorber above said secondspring seat mount, each said at least one spacer having a uniform axialheight; f. placing said second spring seat plate on an uppermost of saidat least one spacer; g. replacing said second spring on said secondspring seat plate; and h. installing said second strut assembly in saidvehicle.
 12. The method of claim 11 comprising the additional steps of:i. determining a first distance by which the height of said vehicle isto be raised; and j. placing a first set of said at least one spacer onsaid second shock absorber, wherein the total height of said first setis about equal to said first distance.
 13. The method of claim 11comprising the additional steps of: i. determining a second distance bywhich the height of said vehicle is to be lowered; and j. placing asecond set of said at least one spacer on said second shock absorber ,wherein the total height of said second set is about equal to saidsecond distance.
 14. The method of claim 11 wherein each spacer has thesame height.
 15. The method of claim 11 wherein each spacer has adifferent height.
 16. The method of claim 11 further comprising the stepof placing a plurality of spacers between said second spring seat mountand said second spring seat plate.
 17. The method of claim 16 whereinsaid plurality of spacers are selected from the group of a spacer with afirst height, a spacer with a second height, and combinations thereof.18. The method of claim 11 wherein rotation of said at least one spacerdoes not affect vehicle ride height.
 19. The method of claim 11 whereinsaid second spring seat mount has an upper surface for abutting one ofsaid spacers, said upper surface being perpendicular to an axis of saidsecond strut assembly.
 20. A method for adjusting the ride height of avehicle from a first ride height comprising: a. replacing an first shockabsorber of the vehicle with a second shock absorber having a fixedlyattached spring seat mount, said spring seat mount having a lowerposition on said second shock absorber than a spring seat mount on saidfirst shock absorber, wherein said second shock absorber is operable toadjust a ride height of said vehicle to a second ride height from saidfirst ride height, said second ride height being lower than said firstride height; b. slidably placing at least one spacer on said secondshock absorber above said fixedly attached spring seat mount, each suchspacer having a uniform axial height to adjust a height of said vehiclein a range from between said second ride height to above said first rideheight; c. placing a spring seat plate on an uppermost of said at leastone spacer; and d. installing said second shock absorber in saidvehicle.
 21. The method of claim 20 further comprising the step ofplacing a plurality of spacers between the spring seat mount and thespring seat plate of said second shock absorber.
 22. The method of claim21 wherein said spacers are inserted between the spring seat plate andthe spring seat mount without removing the spring seat mount from thestrut assembly.
 23. The method of claim 21 wherein said spacers areinserted between the spring seat plate and the spring seat mount withoutremoving the spring seat mount from the second shock absorber.
 24. Themethod of claim 20 wherein the spring seat mount of said second shockabsorber has a substantially flat upper surface.
 25. The method of claim20 wherein rotation of said at least one spacer does not affect vehicleride height.
 26. The method of claim 20 wherein said spring seat mounthas an upper surface for abutting one of said spacers, said uppersurface being perpendicular to an axis of said second strut assembly.27. A method for adjusting the ride height of a vehicle comprising: a.removing a strut assembly from the vehicle; b. removing a spring from ashock absorber of said strut assembly; c. removing a spring seat platefrom said shock absorber; d. slidably placing at least onenon-adjustable spacer on said shock absorber above a fixedly attachedspring seat mount, said spring seat mount comprising a lip around saidshock absorber, said lip having an outside perimeterwherein eachnon-adjustable spacer has a central opening therein having an internaldiameter that is smaller than the outside perimeter of said lip, e.placing said spring seat plate on an uppermost of said at least onespacer; f. replacing said spring on said spring seat plate; and g.installing the strut assembly in said vehicle.
 28. The method of claim27 wherein each of said spacers has an outside perimeter that is greaterthan the outside perimeter of said lip.
 29. The method of claim 27wherein rotation of said at least one spacer does not affect vehicleride height.
 30. The method of claim 27 wherein said spring seat mounthas an upper surface for abutting one of said spacers, said uppersurface being perpendicular to an axis of said shock absorber of saidstrut assembly.